The invention relates to a device for assembling a vehicle window glass with a contiguous element.
Beautifully finished vehicles are known having a profiled sealing strip covering and sealing a slot between the lower edge of their windshield and an element contiguous therewith.
Document DE 37 02 555 C2 describes a cover plate for covering a region between a bonded windshield and a contiguous part of the bodywork. The cover plate is fixed to the windshield in this instance using a U-shaped rail fixed to an edge of the windshield, and in which the cover plate engages. Because the fixing parts are assembled with the cover plate by a flexible assembly leaf that is able to move over at least one side with respect to their transverse dimension, it is necessary to compensate for any tolerances and expansions of the materials that might exist.
Such U-profile sealing strips are also used, for example, to fix to the windshield a water tray covered by the engine hood and which is used to remove the water that runs off the windshield. The U-profile sealing strip surrounds the lower edge of the window glass on three sides and is fixed by gripping or nesting. Fashioned along its side moving away from the edge of the glass is a longitudinal groove into which an edge of the water tray can be inserted. Aside from the sealed transition between the windshield and the water tray, certain mutual support is also thus afforded. The U-profile sealing strip is made of a relatively hard material, generally rubber or plastic, with steel reinforcements so that it can withstand the high forces exerted when the water tray is fixed to the windshield and when the vehicle is running and causing thermal expansion and vibration. The hard material does, however, have the major disadvantage in that the U-profile sealing strip cannot exactly follow the curved path when being fit to the edge of vehicle window glass that is curved in three dimensions. The U-profile sealing strip instead has a tendency to twist, and its longitudinal groove then moves off its theoretical path so that inserting the edge of the water tray becomes very difficult and the precise fitting of the edge of the water tray along the edge of the window glass is made impossible. Likewise, because of the inevitable variations in the dimensions of the window glasses and bodyworks, it is difficult to always guarantee that the profiled sealing strip, which is a prefabricated molding, will always fit properly on the edge of the window glass, thus resulting in lower holding forces and increased slots and tolerances.
Various methods are known for equipping a window glass with an extruded peripheral profile, which rests against just one main face and against the end face of the window glass (DE 43 26 650 A1, DE 42 32 554 C1). These peripheral profiles can be produced in such a way that they form a continuous surface continuation of the untouched main face of the window glass, situated in the plane of the window glass.
Document DE 43 26 650 A1 discloses a method for manufacturing a window glass provided with an overmolded polymer surround. In this instance, the surround is overmolded over the edge of the window glass, using an extrusion die surrounding the window glass and guided along the edge of the window glass by an automatic manipulator, in such a way that the profiled strip is deposited at least on a main face and on the peripheral face of the window glass. During the extrusion operation, the window glass is held stationary with the aid of a support device corresponding to the shape of the window glass, so that the edge of the window glass protrudes freely beyond the bearing faces of the support device.
Document DE 42 32 554 C1 also describes a relevant method, in which the window glass is placed on a heated molded base which presses against the underside of the window glass in the region of the edge thereof. The molded face forms a continuation of the surface of the window glass, beyond the peripheral face of the window glass. Using a remote automatic manipulator and a heated calibrated extrusion die, a profiled strip is deposited along the edge of the window glass with defined exterior dimensions protruding beyond the peripheral face of the window glass. The profiled strip is made of a thermoplastic polymer and is supplied to the extrusion die by an extruder and a flexible pipe heated under pressure.
In the case of the first mentioned method, the extrusion die forms, with the two main faces of the window glass, a closed die cross section and, in the second method, the closed die cross section is formed by the molded base, the freely accessible surface of the window glass and the extrusion die. The two methods have proved suitable for manufacturing car windows which are designed to be mounted by bonding. A surround with an essentially L-shaped cross section, which is provided with a sealing lip, is extruded over part of the periphery or all of the periphery of the window glass. The first branch of the L-shaped surround covers the surface of the window glass that faces the mounting flange, and the second branch forms the continuation of the peripheral face. The sealing lip can be fashioned with equal ease on either of the branches of the surround.
Such peripheral profiles can also be produced using the widely used injection-molding method as described, for example, in documents EP 0 127 546 A1 and EP 0 145 443 B1. It also has been proposed that peripheral profiles be prefabricated using an injection-molding method and then bonded onto the window glass (EP 0 742 762 B1).
There is a need for an improved device for assembling a fixed-mount vehicle window glass with a component contiguous with one edge of the vehicle window glass, particularly a water tray.
The invention relates to a device for assembling a fixed-mount vehicle window glass, particularly a windshield, with a component contiguous with one edge of the vehicle window glass, particularly a water tray. In particular, the exterior surface of a profiled part or strip is bonded and adhered to the vehicle window glass with a lip which joins smoothly and continuously with the free exterior main face of the vehicle window glass. At the same time there is provided, on the underside of the lip, means of assembly with another component. Such a configuration with a continuous surface makes it possible, for example, to bring the windshield wipers to their rest position over the water tray without the need for providing expensive devices for raising the wipers and moving them over any protrusions.
Such a profiled strip may be manufactured in a particularly simple way by extruding a polymer, for example, from either polyurethane systems with a moisture-curing component, polyurethane systems based on two components, thermoplastic elastomers or olefins. To extrude a profiled strip that forms a connection of continuous surface, it is possible for example to use a die surrounding the edge of the window glass, and which is configured to delimit, with the window glass, the extrusion cross section. This means that the die, along the two sides of the window glass, needs to have sealing faces which slide along the main faces of the window glass and make a good seal of the cross section of the die with respect to the surfaces of the glass. The surface of the glass, naturally, cannot be damaged by this sliding. This is possible by using appropriate materials for the die and for the sealing faces of the die, respectively.
In order to endow the profiled part with regions that have different properties in a single operation, recourse may be had to the coextrusion method. In this instance, at least two partial profiled strips are combined into a single profiled strip in the extrusion die.
The two partial profiled strips are thus made, for example, of two different plastic materials having different hardnesses. The two partial profiled strips, for example, also may be made of two different plastic materials having different densities. However, it is just as possible for coextrusion to be used to give a profiled strip, made of one single polymer material, a foamy region using a physical or chemical foaming technique. It is thus possible on the one hand, to provide a material of relatively stable shape for that part of the lip which is assembled with another component, while on the other hand, provide the interior face of the profiled strip, which presses against the bodywork, with properties of flexibility and elasticity in order to suppress noise and compensate for tolerances.
Given that vehicle window glasses designed to be bonded into a bodywork opening are often given a sealed surround or covering of extruded polymer, the extrusion method is also recommended for manufacturing the profiled strip intended for the assembly device according to the invention. The materials, the tools and the devices already exist, which means that production can be economical. When the vehicle window glass is equipped with a sealed surround or covering made of extruded polymer and with a profiled part for assembling it with a contiguous component, the profiled part forms a portion of the surround. The profiled part and the surround may be manufactured in a single operation using corresponding extrusion dies, and the transition regions between the start and the end of the extruded profiled strip may be fashioned using known methods (DE 44 45 258 A1).
The profiled part may, however, also be deposited by spraying onto the window glass in a way known per se, by placing the window glass between two half molds, in which molding cavities corresponding to the desired shape or profile are machined, and by filling the cavities, once the half molds have been closed, with a molten thermoplastic polymer or with a reactive polymer system. In the same way, it is also possible to manufacture just the profiled part as an injection-molding and for it then to be bonded afterwards onto the edge of the window glass.
Advantageously, the profiled part is provided, on its face that is facing the bodywork, with a region which rests on and is supported by part of the bodywork. Thus, not only is the stability of the assembly device improved, but the sealing between the vehicle window glass and the bodywork may also be improved. Said region may, for example, be in the form of an elastic bearing lip or a protruding polymer foam elastic bead or profile.
It is often necessary for the component to be demountably assembled with the profiled part so that it may be dismantled. It then becomes possible for assemblies installed under the component, such as a top-up battery or wiper motor, to be serviced or repaired. One demountable assembly often used is the clip-fastened assembly, in which a part with a barbed hook shape, provided with inverse hooks, is introduced into an undercut groove. To dismantle this assembly, significant forces need to be employed or special tools need to be used. Other demountable assembles may be achieved with a hook-type closure or with a deactivatable bonded assembly. The dismantleable assemblies may extend over the entire length of the profiled part parallel to the lower edge of the window glass. However, it is just as possible for the assembly elements to be arranged in several limited areas spaced apart.
Other details and advantages of the subject of the invention will become apparent from the drawings of an exemplary embodiment, with no intention of limiting, and from their detailed description which follows.